Social Explorer; U.S. Census Bureau; Census of Population and Housing, 1980: Summary Tape File 3 [machine-readable data file] / conducted By the U.S. Bureau of the Census. Washington: Bureau of the Census [producer and distributor], 1982.

As indicated on the questionnaire and in instructions to respondents, regular school or college includes nursery school, kindergarten, elementary school and schooling which leads to a high school diploma or college degree. Attendance can be either by day or night, full time or part time, to be counted as regular schooling. Enrollment in a trade or business school, company training, or tutoring was counted if the course would be accepted for credit at a regular elementary school, high school, or college.

Persons were excluded from the enrollment figures if the only schools they bad been attending at any time since February 1, 1980, were not "regular" (unless courses taken at such schools could have been counted for credit at a regular school). Schools regarded as not "regular" may include nursery schools which simply provide custodial day care; specialized vocational, trade, or business schools outside the "regular" system, such as television repair schools, barber's colleges, or typist's training schools; on-the-job training; and correspondence courses.

Questions on schooling have been included since 1930, although the time reference varied until 1950 when February 1 to the time of enumeration was adopted as the reference period. Most tabulations of school enrollment in 1970 were restricted to persons 3 to 34 years old, whereas most 1980 tabulations do not have an upper age limit.